The TAB is trying to contact and reimburse customers whose bets were affected during a recent power outage.
A power supply failure about 2.45pm on January 17, caused two servers at the TAB's Petone data centre to close down for about two hours, affecting betting on two races - Morrinsville Harness Race 9 and Auckland Greyhound Race 4.
New Zealand Racing Board chief executive Andrew Brown apologised for the inconvenience caused to customers and wanted to contact as many affected as possible.
"A small number of customers placed bets after the races jumped, which reduced the dividends for winning customers," Mr Brown said.
"For this reason, we're trying to contact those winning customers to pay the increased dividend. We also want to contact any customers who placed losing bets after the jump, because they will be entitled to a refund. We want to ensure everyone affected is appropriately compensated.
"We have already begun reimbursing affected TAB account customers and are now trying to contact cash customers."
TAB cash customers whose bets were impacted by the power failure should complete a lost ticket claim form.
Mr Brown said the TAB had made changes to its power supply in the data centre to prevent a similar incident happening again.
